If you have multi warehouses it's possible to restrict warehouse users to only see data from certain warehouses.
You have a picker that works in one warehouse. They have no interest is seeing orders and stock for other depots that they don't work in.
This can be done using the Manage Warehouse Access option:
By Default the User will have access to all Warehouses:
You can then remove access to any warehouse that they don't need
e.g. User Only has access to the Chelmsford Warehouse